JP2889799B2 - Heat pump equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a state in which a high-pressure gas refrigerant supply path and a condensed refrigerant outlet path are communicated with a heat exchanger so that the heat exchanger functions as a condenser (hereinafter simply referred to as "condenser state"). ), And a state where the expanded refrigerant supply passage from the expansion means and the low-pressure gas refrigerant outlet passage are communicated with the heat exchanger so that the heat exchanger functions as an evaporator (hereinafter simply referred to as “evaporator”). The present invention relates to a heat pump device provided with control means for switching control of the refrigerant path.

[0002]

2. Description of the Related Art Conventionally, in a heat pump apparatus of this type, when a heat exchanger is switched between a condenser state and an evaporator state, a control means temporarily supplies a high-pressure gas refrigerant supply path, a condensed refrigerant discharge path, and an expanded refrigerant supply path. After all of the passages and the low-pressure gas refrigerant outlet passages are not communicated with the heat exchanger, the heat exchange is performed simultaneously on the expansion refrigerant supply passage and the low-pressure gas refrigerant outlet passage, or on the high-pressure gas refrigerant supply passage and the condensed refrigerant outlet passage. It was configured to communicate with the heat exchanger to allow the refrigerant to flow through the heat exchanger.

[0003]

However, according to the above prior art, after switching all four refrigerant paths to a heat exchanger in a non-communication state during switching, two different refrigerant paths different from the previous one are simultaneously connected. When communicating, due to a sudden flow in the heat exchanger refrigerant flow with a large difference in height from the previous internal pressure in the heat exchanger,
There was an inconvenience of generating noise.

In the case of switching from the condenser state to the evaporator state, in the prior art, all the four refrigerant paths are brought into a non-communication state with the heat exchanger, and then the expanded refrigerant supply path and the low-pressure gas refrigerant are led out. At the time when the passages are simultaneously connected to the heat exchanger, the condensed refrigerant before the switching still remains in the heat exchanger. And the operating efficiency is reduced.

An object of the present invention is to eliminate the above-mentioned conventional disadvantages.

[0006]

A first feature of the heat pump device according to the present invention is that the control means causes the heat exchanger to function as a condenser from a state of functioning as a condenser (condenser state). When switching to the (evaporator state), all of the high-pressure gas refrigerant supply path, the condensed refrigerant outlet path, the expanded refrigerant supply path, and the low-pressure gas refrigerant outlet path are brought into a non-communication state with the heat exchanger. The low-pressure gas refrigerant lead-out path is communicated with the heat exchanger ahead of the expansion refrigerant supply path, and the expanded refrigerant supply path is thereafter configured to communicate with the heat exchanger. There is in the point.

[0007] A second characteristic configuration of the heat pump device according to the present invention is that the control means switches from a state in which the heat exchanger functions as an evaporator (evaporator state) to a state in which the heat exchanger functions as a condenser (condenser state). When performing the switching, the high-pressure gas refrigerant supply path, the condensed refrigerant outlet path, the expansion refrigerant supply path, all the low-pressure gas refrigerant outlet path to the non-communication state to the heat exchanger, after the condensed refrigerant outlet path Also, the configuration is such that the high-pressure gas refrigerant supply path is communicated with the heat exchanger in advance, and then the condensed refrigerant outlet path is communicated with the heat exchanger.

[0008]

According to the first characteristic configuration of the present invention, when the heat exchanger is switched from the condenser state to the evaporator state, the low-pressure gas refrigerant outlet path is communicated before the expanded refrigerant supply path, Before the expanded refrigerant flows into the heat exchanger, the high-pressure gas refrigerant and the condensed refrigerant remaining in the heat exchanger are led out from the low-pressure gas refrigerant outlet passage, and the inside of the heat exchanger is brought into a low-pressure state.

According to the second feature, when the heat exchanger is switched from the evaporator state to the condenser state, the high-pressure gas refrigerant supply path is communicated in advance of the condensed refrigerant outlet path. Before the inside becomes a flow state of the high-pressure gas refrigerant or the condensed refrigerant, the inside of the heat exchanger is compressed by the pressure from the high-pressure gas refrigerant supply path, and the inside of the heat exchanger becomes a high-pressure state.

[0010]

According to the first aspect of the present invention, when the heat exchanger is switched from the condenser state to the evaporator state, before the expanded refrigerant is passed through the heat exchanger, the heat exchanger is turned on. Is in a low pressure state, and the remaining condensed refrigerant is also removed, so that the previous generation of noise at the time of switching to the evaporator state and the reduction in operating efficiency due to a reduction in the refrigerant circulation amount are effectively eliminated.

According to the second aspect of the present invention, when the heat exchanger is switched from the evaporator state to the condenser state,
Before the high-pressure gas refrigerant or the condensed refrigerant flows into the heat exchanger, the internal pressure of the heat exchanger becomes high, so that the previous generation of noise when switching to the condenser state is effectively eliminated. .

[0012]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 show a separate type air conditioner,
Is an outdoor unit and Ui is an indoor unit. The outdoor unit Uo and the indoor unit Ui are a high-pressure gas pipe Gh flowing through a high-pressure gas refrigerant Rh and a low-pressure gas pipe Gc flowing through a low-pressure gas refrigerant Rc.
And a liquid pipe W through which the liquid refrigerant Rw flows.

The outdoor unit Uo includes a first heat exchanger N1 and a second heat exchanger N2 for absorbing and releasing heat to and from the outside air OA, and an outside air OA to the first and second heat exchangers N1 and N2. The outside air fans F1 and F2, the compressor Cmp and the accumulator Ac, the receiver R, the first expansion valve ex1 for the first heat exchanger N1, and the second expansion valve ex2 for the second heat exchanger N2 are provided. Provided.

The indoor unit Ui has a first air supply fan F3 for supplying air supply SAp to the perimeter zone Peri through the air supply duct da, and a second air supply fan F1 for supplying air supply SAi to the interior zone Inte through the air supply duct db. Two-supply fan F4
A third heat exchanger N3 for adjusting the air supply SAp to the perimeter zone Peri, and an upstream fourth heat exchanger N4 for adjusting the air supply SAi to the interior zone Inte.
And a fifth heat exchanger N5 on the downstream side, a third expansion valve ex3 for the third heat exchanger N3, a fourth expansion valve ex4 for the fourth heat exchanger N4, and a fifth expansion valve ex5 for the fifth heat exchanger N5. And a return air duct dc for guiding return air RA from the interior zone Inte and the perimeter zone Peri is connected.

V1 to v9 correspond to the condenser C among the first to fifth heat exchangers N1 to N5 according to the operation mode described later.
This is a switching valve for selectively switching between a function that functions as d, a function that functions as the evaporator Ev, and a function that stops and stops the passage of the refrigerant.

The valve vR of the outdoor unit Uo determines whether the first and second heat exchangers N1 and N2 allow refrigerant to pass through both the first and second heat exchangers N1 and N2, By switching the refrigerant path to a state in which the passage of the refrigerant to the heat exchanger N2 is interrupted and the refrigerant is passed only to the first heat exchanger N1, the communication between the first and second heat exchangers N1 and N2 and the outside air OA as a whole is changed. A switching valve for switching the heat exchange capacity, and vc is a check valve.

The first to fifth expansion valves ex1 to ex5 function as original refrigerant expansion means when the liquid refrigerant Rw flows toward the heat exchangers N1 to N5 corresponding to the respective valves. When the liquid refrigerant Rw flows toward the side away from each of the corresponding heat exchangers N1 to N5, it is configured to simply function as a flow control valve. Further, each of the first to fifth expansion valves ex1 to ex5 is provided with a valve closing means, and is configured to be able to cut off the flow of the refrigerant.

The fourth heat exchanger N4 and the fifth heat exchanger N5 of the indoor unit Ui are connected to the fifth heat exchanger N on the downstream side in the air flow direction.
5 is made to function as a condenser Cd, and the fourth heat exchanger N4 on the upstream side in the air flow direction is made to function as an evaporator Ev, so that the reheat dehumidification temperature control operation for the interior zone Inte can be performed. ing.

The outdoor unit Uo is provided with a control unit H for controlling various operation operations of the separate air conditioner.
The control unit H is mainly configured by a microcomputer, and is configured to perform various control operations by software incorporated therein.

The temperature T of the supply air SAp is supplied to the supply air duct da.
A temperature sensor S3 for detecting p is provided. The air supply duct db is provided with a temperature sensor S4 for detecting the temperature Ti of the air supply SAi. The return air duct dc is provided with a temperature sensor S5 for detecting the return air temperature Tr of the return air RA from the perimeter zone Peri and the interior zone Inte.

A pressure sensor S8 for detecting the pressure Ph of the high-pressure gas refrigerant is provided on the discharge side of the compressor Cmp, and a pressure sensor S9 for detecting the pressure Pc of the low-pressure gas refrigerant is provided on the suction side of the compressor Cmp. Is provided.

FIG. 1 shows that the first and second heat exchangers N1 and N2 of the outdoor unit Uo function as an evaporator Ev, and the third and fourth heat exchangers N3 and N3 of the indoor unit Ui. N4
Function as a condenser Cd to absorb heat from the outside air OA while supplying air to the perimeter zone Peri.
In addition, the operation state of the “heating mode” in which the supply air SAi to the interior zone Inte is heated and temperature-controlled is shown.

As a specific refrigerant flow, a high-pressure gas refrigerant Rh (shown by a thick black line in the figure) compressed by the compressor Cmp is sent to the indoor unit Ui through a high-pressure gas pipe Gh. The heat is distributed and supplied to the three heat exchangers N3 and the fourth heat exchanger N4 to be condensed, and the heating temperature is adjusted.

The distribution ratio of the high-pressure gas refrigerant Rh to the third heat exchanger N3 and the fourth heat exchanger N4 is adjusted by adjusting the degree of opening of the third expansion valve ex3 and the fourth expansion valve ex4 functioning as flow control valves. Have been.

The condensed liquid refrigerant Rw (shown by a thick line with hatching in the figure) sent from the third heat exchanger N3 and the fourth heat exchanger N4 is supplied to the third expansion valve ex3 or ex3 which functions as a flow control valve. After passing through the fourth expansion valve ex4, they are merged again, fed through the liquid pipe W to the outdoor unit Uo, and distributed and depressurized by the first expansion valve ex1 and the second expansion valve ex2 functioning as the original refrigerant expansion means. After being expanded, it is evaporated in the first and second heat exchangers N1 and N2, and heat is absorbed from the outside air OA.

The low-pressure gas refrigerant Rc (shown by a thick white line in the drawing) sent out from the first and second heat exchangers N1 and N2 is again joined and then sent to the accumulator Ac, where it is sent to the compressor Cmp Is returned to. (Note that, in the figure, a black valve indicates a closed state.)

As an operation mode of the air conditioner by the control unit H, the first and second heat exchangers N1 and N2 are made to function as a condenser Cd for radiation, in addition to the above-mentioned "heating mode".
The "cooling mode" in which the third and fourth heat exchangers N3 and N4 function as cooling evaporators Ev, the first and second heat exchangers N1 and N2 function as heat dissipation condensers Cd, and the third and fourth heat exchangers N1 and N2 function as heat dissipation condensers Cd. One of the four heat exchangers N3 and N4 is made to function as a condenser Cd for heating, and the other is used as an evaporator Ev for cooling.
"Cooling / heating simultaneous mode" in which the first and second heat exchangers N1 and N2 function as the endothermic evaporator Ev, and the fourth heat exchanger N4 as the dehumidifying evaporator Ev. "Reheat dehumidification mode" in which the fifth heat exchanger N5 functions as the heating condenser Cd, and the air supply fans F3, F without operating the heat pump device.
4 is configured so that a "ventilation mode" in which only ventilation is performed for the interior zone Inte and the perimeter zone Peri can be performed.

FIG. 5 shows an air supply duct da and an air supply duct d.
b and the perimeter zone Peri and the interior zone Int connected to the indoor unit Ui by the return air duct dc.
e is shown. The air supply duct da and the branch connection path of the air supply duct db to the perimeter zone Peri and the interior zone Inte are provided with a plurality of variable air flow devices for adjusting the air supply amount of the air supply SAp or the air supply SAi by adjusting the opening degree of the damper, respectively. Vav1 or Vav2 is provided.

In the variable air volume devices Vav1 and Vav2,
Controller cv1 or cv for adjusting the opening of the damper
2, an air volume sensor S6 or S7 for detecting the air volume Q,
A temperature sensor S1 or S2 for detecting the temperature of each air conditioning target area and a target temperature setting device r1 or r2 for setting a target temperature of each air conditioning target area are provided.

When the supplied air supply SAp or SAi is at the heating temperature control, the controllers cv1 and cv2 are shown in FIG.
If the supplied air supply SAp or SAi is controlled for cooling temperature, the detected temperature of the temperature sensor S1 or S2 and the set target of the target temperature setter r1 or r2 are determined according to the graph shown in FIG. The target air volume Qm is set based on a deviation Δt from the temperature (detected temperature−set target temperature). Each of the plurality of variable air volume devices Vav1 and Vav2 is configured to independently increase or decrease the damper opening so that the detected air volume Q becomes the target air volume Qm.

The controllers cv1 and cv2 are:
The control unit H included in the outdoor unit Uo is configured to transmit various control information, which will be described later.

As shown in FIG. 8, the control unit H has a set air supply function for setting and changing the set air supply temperature Tsi of the air supply SAi and the air supply temperature Tsp of the air supply SAp. Temperature control means 101 and set air supply temperature control means 10
The operating capacity control means 102 adjusts the operating capacity of the heat pump device based on the set air supply temperatures Tsi and Tsp set in Step 1, the return air temperature Tr of the return air RA, and the set air supply temperature T.
An operation mode switching means 103 for switching the operation mode of the heat pump device based on si and Tsp is configured. In addition, the control unit H is configured to control the operation of various devices and various valves to start and stop the operation, perform a defrosting operation, and the like.

The set air supply temperature control means 101 determines the set air supply temperature of the air supply SAp based on information indicating the room temperature state of the perimeter zone Peri or interior zone Inte sent from each of the controllers cv1 and cv2. It is configured to change and adjust the set supply temperature Tsi of Tsp and the supply air SAi.

As shown in FIG. 9, the information indicating the state at room temperature is composed of one of three types of signals, "OVER", "insufficient", and "OK", and the target air volume of the controller cv1 or cv2. Assigned according to the state of Qm. However, the “OVER” signal is output from the controller cv1
Alternatively, when cv2 controls the air volume Q during the heating temperature control (that is, when the target air volume Qm is set according to FIG. 6), it indicates that the room temperature is higher than the set target temperature by 1 ° C. or more. When the air volume Q during cooling temperature control is controlled (that is, when the target air volume Qm is set according to FIG. 7), it indicates that the room temperature is lower than the set target temperature by 1 ° C. or more. . As in the case described above, the "insufficient" signal also has a different room temperature state depending on whether the heating temperature is controlled or the cooling temperature is controlled. The “deficient” signal is directly assigned to the variable air volume device that is forcibly set to the maximum air volume, and the signal of the variable air volume device in the forced fully closed state is, as described later, a signal of the set supply air temperature Tsi, Tsp. Ignored in control.

The control of the set supply temperature Tsp of the supply air SAp is performed only by the signal of the controller cv1, and the control of the set supply temperature Tsi of the supply air SAi is performed only by the signal of the controller cv2.

The set air supply temperature control means 101 changes and adjusts the set air supply temperature Tsp of the air supply SAp and the set air supply temperature Tsi of the air supply SAi according to the flowchart shown in FIG. First, as shown in step 1, all controllers cv1 or all controllers cv2
As the signal is received, the content of the signal is inspected, and as shown in step 2, the forced air volume device Vav1 in the forced fully closed state
Alternatively, the number of Vav2s is measured, and the remaining number obtained by subtracting the number in the forced fully closed state from the total number is set to 100%. Then, as shown in step 3, a percentage value x of the number of vehicles in the forced fully closed state is obtained.

Next, as shown in step 4, "OVE
R, the number of “OVER” signals is calculated, and a percentage value “a” of the number of “OVER” signals is calculated. Is calculated.

Then, as shown in Step 6, y is
Substituting 2 as a priority multiple when the “OVER” signal and the “insufficient” signal are simultaneously input, and when a ≧ x and a ≧ y · b as shown in steps 7 and 8, As shown in step 9, if the heating temperature control (heating) is controlled, the set supply temperature Tsi or Tsp is decreased by 1 ° C., if the cooling temperature control (cooling) is controlled, the set supply temperature Tsi or Increase Tsp by 1 ° C.

On the other hand, as shown in Steps 10 and 11, when b ≧ x and b ≧ y · a,
As shown in step 12, if the control is heating temperature control (heating), the set supply air temperature Tsi or Tsp is increased by 1 ° C., if the control is cooling temperature control (cooling), the set supply air temperature Tsi or Tsp is used.
Is lowered by 1 ° C.

In other cases, the current condition is maintained, and the above-described control operation is repeated at predetermined time intervals.
Thus, the set supply temperature Tsp and the set supply temperature Tsp
si is the perimeter zone Peri or interior zone I
Depending on the room temperature condition of the nte, it is always adjusted automatically.

As shown in FIG. 8, the operating capacity control means 102 sets the temperature Tp of the supply air SAp to the set supply air temperature Tsp based on the detection information of the temperature sensors S3 and S4, and The rotation speed of the compressor Cmp and the opening degrees of the first to fourth expansion valves ex1 to ex4 are adjusted so that the temperature Ti of the supply air SAi becomes the set supply temperature Tsi.

In the "heating mode" of the present embodiment shown in FIG. 1, the amount of refrigerant circulating in the heat pump circuit is controlled by adjusting the rotation speed of the compressor Cmp, and the state in which the refrigerant functions as a flow control valve is obtained. By adjusting the opening of the third and fourth expansion valves ex3 and ex4, the distribution ratio of the refrigerant to the third and fourth heat exchangers N3 and N4 is controlled,
By adjusting the respective heating amounts of the third and fourth heat exchangers N3 and N4, the temperatures T of the supply air SAp and SAi are adjusted.
p and Ti are adjusted.

The "cooling mode" can be similarly controlled.

The first and second heat exchangers N1 and N2 are made to function as a condenser Cd for heat dissipation, and the third and fourth heat exchangers N
3 and N4 function as a condenser for heating Cd, and the other functions as an evaporator for cooling Ev.
By controlling the number of rotations of p and controlling the circulation amount of the refrigerant, the cooling amount of the heat exchanger N3 or N4 functioning as the cooling evaporator Ev is adjusted, and the temperature Tp or Ti in the cooling temperature control is reduced. Adjusted. Then, the first and second expansion valves ex1 and ex2 functioning as flow rate adjusting valves and the heating condenser Cd
By adjusting the opening degree of the expansion valve ex3 or ex4 corresponding to the heat exchanger N3 or N4 functioning as a heat exchanger, the distribution ratio of the refrigerant is controlled, and the heat exchanger N3 or N4 functioning as the heating condenser Cd is controlled. The heating amount and the heat radiation amount of the first and second heat exchangers N1 and N2 are adjusted, and the temperature Ti or Tp of the heating temperature controller is adjusted.

In the "cooling / heating simultaneous mode" in which the first and second heat exchangers N1 and N2 function as heat-absorbing evaporators Ev, the heating condenser Cd is similarly controlled by controlling the circulation amount of the refrigerant. The heating amount of the functioning heat exchanger N3 or N4 is adjusted, and by controlling the distribution ratio of the refrigerant, the cooling amount of the heat exchanger N4 or N3 functioning as the cooling evaporator Ev, and the first and second heat exchangers The endothermic amounts of N1 and N2 are adjusted to adjust the temperatures Tp and Ti.

It should be noted that the on / off state of the capacity switching valve vR is switched as required to adjust the heat absorbing and radiating capacity of the first and second heat exchangers N1 and N2.

As shown in FIG. 8, the operation mode switching means 103 first sets the operation mode based on the return air temperature Tr of the return air RA detected by the temperature sensor S5 at the start of the operation of the air conditioner. When the return air temperature Tr is equal to or higher than 25 ° C., the cooling mode is set, and when the return air temperature Tr is equal to or lower than 21 ° C., the heating mode is set.
When the temperature is within the range of 4 ° C., “ventilation mode” is initially set. (Hereinafter, in the present embodiment, all temperatures are handled in digital quantities in increments of 1 ° C. Therefore, for example, less than 25 ° C. and 24 ° C. or less have the same meaning.)

At this time, the set supply air temperature control means 101
Sets the set air supply temperatures Tsp and Tsi to 35 ° C. in the “heating mode”, and 15 ° C. in the “cooling mode”. Thereafter, the set supply air temperatures Tsp and Tsi are automatically changed up and down by 1 ° C. as described above.

The operation mode switching means 103 constantly monitors the return air temperature Tr and the set supply air temperatures Tsp and Tsi, and the set supply air temperature Tsp becomes higher than the return air temperature Tr by a predetermined temperature or more. In this case, the operation mode is switched from the operation mode in which the third heat exchanger N3 functions as the cooling evaporator Ev to the operation mode in which the third heat exchanger N3 functions as the heating condenser Cd.
At the set air supply temperature Tsi, the operation mode of the fourth heat exchanger N4 is similarly switched.

If the set supply air temperature Tsp is lower than the return air temperature Tr by a predetermined temperature or more, the third heat exchanger N
3 is switched from an operation mode in which it functions as the heating condenser Cd to an operation mode in which it functions as the cooling evaporator Ev. Also at the set air supply temperature Tsi, the operation mode of the fourth heat exchanger N4 is similarly switched.

The switching of the first and second heat exchangers N1 and N2, which are the heat exchangers of the outdoor unit Uo, corresponds to the switching to the "cooling mode" or the "heating mode" and will be described later. Thus, in the “simultaneous cooling and heating mode”,
It may be performed at any time according to a change in the magnitude relationship between the amount of condensation of the heating condenser Cd and the amount of evaporation of the cooling evaporator Ev.

The switching of the operation mode is performed by switching the intermittent state of the first to fifth expansion valves ex1 to ex5 and the switching valves v1 to v9, thereby communicating with the first to fifth heat exchangers N1 to N5. This is performed by switching control of the refrigerant path. Hereinafter, from the “heating mode”, the “simultaneous cooling and heating mode” in which the fourth heat exchanger N4 functions as the cooling evaporator Ev
The switching control to the example will be described step by step as shown in FIGS. 1 to 4.

FIG. 1 shows the "heating mode" as described above.
Is shown. The fourth heat exchanger N4 is in a state of functioning as a heating condenser Cd. The switching valve v8 is closed, the switching valve v6 is opened, and the fourth heat exchanger N4
Is supplied with a high-pressure gas refrigerant Rh. In addition, the fourth expansion valve ex4 flows the condensed liquid refrigerant Rw from the fourth heat exchanger N4 in a state where the fourth expansion valve ex4 is open and functions as a flow control valve. Therefore, the high-pressure gas refrigerant supply path and the condensed refrigerant outlet path are connected to the fourth heat exchanger N4.

The operation mode switching means 103 first operates as shown in FIG.
As shown in (5), the switching valve v6 and the fourth expansion valve ex4 are closed, and the operation of the fourth heat exchanger N4 as the heating condenser Cd is stopped.

Next, as shown in FIG. 3, the switching valve v8 is opened, and the low-pressure gas refrigerant outlet path connected to the suction side of the compressor Cmp via the accumulator Ac is connected to the fourth heat exchanger N4. To the communication state. At this time, the fourth expansion valve ex4 is still in the closed state. Fourth heat exchanger N
The refrigerant remaining inside 4 is brought close to a state of a low-pressure gas refrigerant.

Thereafter, as shown in FIG. 4, the fourth expansion valve e
x4, and controls the degree of superheat by controlling it to function as an original expansion valve, and connects the expansion refrigerant supply passage for supplying refrigerant from the expansion valve to the fourth heat exchanger N4. In the communication state, the operation in the “simultaneous cooling / heating mode” in which the fourth heat exchanger N4 functions as the cooling evaporator Ev is started.
In order to adjust the evaporation amount and the condensation amount, the second expansion valve e
x2 and the capacity switching valve vR are closed, and the second heat exchanger N2 is closed.
Is stopped as the endothermic evaporator Ev.

Further, a specific switching procedure when switching from the cooling evaporator Ev to the heating evaporator Ev will be described by taking the fourth heat exchanger N4 shown in FIG. 4 as an example. In FIG. 4, the fourth heat exchanger N4 is connected to the fourth expansion valve N4 as described above.
The expanded refrigerant supply path and the low-pressure gas refrigerant outlet path are communicated with each other depending on the open state of the switching valve v8, and are in a state of functioning as a cooling evaporator Ev.

The operation mode switching means 103 first closes the switching valve v8 and the fourth expansion valve ex4 to stop the operation of the fourth heat exchanger N4 as the cooling evaporator Ev. Next, the switching valve v6 is opened to bring the high-pressure gas refrigerant supply path connected to the discharge side of the compressor Cmp into a state of communication with the fourth heat exchanger N4. At this time, the fourth expansion valve ex4
Is still in the closed state. The refrigerant remaining inside the fourth heat exchanger N4 is brought close to a state of a high-pressure gas refrigerant. After that, the fourth expansion valve ex4 is opened, and the flow rate adjustment control is started, and the condensed refrigerant outlet path for discharging the condensed liquid refrigerant Rw from the fourth heat exchanger N4 is set in a communicating state,
The operation of the fourth heat exchanger N4 as the heating condenser Cd is started.

Similarly, the operation mode switching means 103 switches the first and second heat exchangers N1, N
2. When the third heat exchanger N3 or the fifth heat exchanger N5 is switched, the first and second expansion valves ex1 and ex2, the third expansion valve ex3, and the third expansion valve ex3 corresponding to the respective heat exchangers are also provided. Fifth expansion valve ex5, switching valves v1, v3, switching valve v
4, v5 and the switching valves v7, v9 are switched according to the above-described operation procedure, and the refrigerant paths to be communicated with each other are switched and controlled.

Accordingly, the operation mode switching means 103 connects the high pressure gas refrigerant supply passage and the condensed refrigerant outlet passage to the first, second, third, fourth or fifth heat exchangers N1, N2, N3, N4 or N5. And the heat exchangers N1, N2, N3, N
4 or N5 functions as a condenser Cd, and communicates an expansion refrigerant supply path from first to fifth expansion valves ex1 to ex5 as expansion means and a low-pressure gas refrigerant discharge path to function as an evaporator Ev. And a state in which the refrigerant path is controlled to switch the refrigerant path. When switching from the state in which the condenser Cd functions to the state in which the condenser Cd functions as the evaporator Ev, the high-pressure gas refrigerant supply path and the condensed refrigerant outlet path After all of the expansion refrigerant supply path and the low-pressure gas refrigerant lead-out path are in a non-communication state with respect to the heat exchangers N1, N2, N3, N4 or N5, the low-pressure gas refrigerant lead-out path is set to a lower position than the expansion refrigerant supply path. Prior to the heat exchanger N1, N
2, N3, N4 or N5, and then connect the expanded refrigerant supply path to the heat exchangers N1, N2, N5.
3, N4 or N5, and when switching from the state of functioning as the evaporator Ev to the state of functioning as the condenser Cd, the high-pressure gas refrigerant supply path, the condensing refrigerant outlet path, All of the expansion refrigerant supply path and the low-pressure gas refrigerant discharge path are connected to the heat exchangers N1, N
2, after making it incommunicable with N3, N4 or N5,
The high-pressure gas refrigerant supply path is communicated with the heat exchanger N1, N2, N3, N4 or N5 prior to the condensed refrigerant discharge path, and thereafter the condensed refrigerant discharge path is connected to the heat exchanger N1. , N2, N3, N4 or N5.

In this embodiment, the operation mode switching means 1
03 controls the switching of the operation mode in which the third heat exchanger N3 and the fourth heat exchanger N4 are switched according to the flowchart shown in FIG. The switching from the heating condenser Cd to the cooling evaporator Ev of the third heat exchanger N3 or the fourth heat exchanger N4 is performed by returning the set supply temperature Tsp or Tsi as shown in steps 3 and 4. This is performed as the temperature becomes lower than the temperature Tr by 1 ° C. or more. However, at this time, the third or fourth expansion valve ex3 or ex4 is still in the closed state. Then, as shown in Step 7, the set supply air temperature Tsp or Tsp
As si continues to decrease further and becomes lower than the return air temperature Tr by 3 ° C. or more, as shown in Step 8, the third or fourth expansion valve ex3 or ex4 is opened and the original expansion valve is opened. Control to a functioning state, start superheat control, and start cooling operation.

The switching from the cooling evaporator Ev to the heating condenser Cd is performed as shown in Steps 5 and 6, when the set supply air temperature Tsp or Tsi is one more than the return air temperature Tr.
It is performed as the temperature rises by more than ℃. However, at this time, the third or fourth expansion valve ex3 or ex4 is still in the closed state. Then, as shown in step 9, the set supply air temperature Tsp or Tsi continues to further increase, and becomes 3
As the temperature rises by more than ℃, as shown in step 10,
The third or fourth expansion valve ex3 or ex4 is opened, the flow rate adjustment control is started, and the heating operation is started.

When the switching control of the third and fourth heat exchangers N3 and N4 is summarized with respect to the temperature, as shown in FIG. 12, the switching control is performed based on the detected return air temperature Tr detected by the temperature sensor S5. When the supply air temperature Tsp or Tsi set by the air supply temperature control means 101 becomes higher or lower by 1 ° C. or more than the detected return air temperature Tr, the operation mode switching is started, and
The heating operation or the cooling operation is started when the temperature rises or falls by more than ° C. Therefore, the range of 2 ° C above and below the detected return air temperature Tr is a dead zone of the switching control. (However, all temperatures are handled in digital quantities in 1 ° C increments.)

In this embodiment, the operation mode switching means 103 sets the outdoor unit U in the “simultaneous cooling / heating mode”.
o, ie, the first and second heat exchangers N1,
The operation state of N2 is controlled according to the flowchart shown in FIG. The operation mode switching means 103 performs step 1
As shown in (1), the opening of the first and second expansion valves ex1 and ex2 is monitored, and the opening is the lower limit (for example, 20% or less).
, The detected pressure Ph of the high-pressure gas refrigerant Rh detected by the pressure sensor S8 as shown in step 2.
And the detected pressure Pc of the low-pressure gas refrigerant Rc detected by the pressure sensor S9 are stored in the memory as the storage pressure Phm and the storage pressure Pcm, respectively.

Thereafter, as shown in step 3, the timer waits until one minute elapses, and after one minute elapses, the pressure Ph of the high-pressure gas refrigerant Rh and the pressure Pc of the low-pressure gas refrigerant Rc are checked again. If the detected pressure Ph is higher than the storage pressure Phm as shown in Step 4, the first and second heat exchangers N1 and N2 are connected to the condenser Cd as shown in Step 5. If the detected pressure Pc has fallen below the stored pressure Pcm as shown in step 8, as shown in step 9,
The first and second heat exchangers N1 and N2 are switched to the endothermic evaporator Ev. However, at this time, the first and second expansion valves ex
1 and ex2 are still in the valve closed state.

Then, as shown in steps 6 and 10, the timer waits for another one minute to elapse, and after one minute elapses, as shown in step 7 or step 11, the first and second expansion valves ex1 and ex1. open ex2,
At the same time, the flow rate control or the superheat control is started.

In steps 4 and 8, if neither increase in the pressure Ph of the high-pressure gas refrigerant Rh nor decrease in the pressure Pc of the low-pressure gas refrigerant Rc is detected.
Returning to step 1, the first and second heat exchangers N1, N2
Is maintained as it is.

[Alternative Embodiment] In this embodiment, each of the first to fifth heat exchangers N1 to N5 is connected to two refrigerant pipes, and has a high-pressure gas refrigerant supply path, a low-pressure gas refrigerant outlet path, and ,
Although the condensed refrigerant outlet path and the expanded refrigerant supply path are shared by the same refrigerant pipe, each is constituted by separate refrigerant pipes (four in total),
A switching valve may be provided for each refrigerant pipe. Only one of them may be used, and a total of three may be used.

First to fifth expansion valves ex1 as expansion means
Although ex5 is also used as a switching means for switching the condensed refrigerant outlet passage or the expanded refrigerant supply passage between the communicating state and the non-communicating state, a switching valve may be separately provided.

The switching control of the operation mode of the operation mode switching means 103 is not limited to the above-described control mode, and the control mode of the switching temperature, the dead zone width, the set supply air temperature and the like can be appropriately changed. However, the switching procedure of the refrigerant path is based on the procedure of the present invention.
The operation mode is switched by the operation mode switching means 103.
However, the operation may not be performed automatically, but may be performed forcibly by manual operation.

The configuration of the air-conditioning target area of the air conditioner and the configuration of the interior zone Inte perimeter zone Peri can be changed as appropriate.

In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration shown in the attached drawings.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an overall configuration of an air conditioner.

FIG. 2 is a configuration diagram showing the overall configuration of the air conditioner.

FIG. 3 is a configuration diagram showing the overall configuration of the air conditioner.

FIG. 4 is a configuration diagram showing the overall configuration of the air conditioner.

FIG. 5 is a configuration diagram showing an interior zone and a perimeter zone.

FIG. 6 is a graph showing a target air volume of the variable air volume device.

FIG. 7 is a graph showing a target air volume of the variable air volume device.

FIG. 8 is a block diagram showing a control unit.

FIG. 9 is a table showing information indicating a state at room temperature.

FIG. 10 is a flowchart of set air supply temperature control.

FIG. 11 is a flowchart of operation mode switching control.

FIG. 12 is an explanatory diagram showing operation mode switching control.

FIG. 13 is a flowchart of the outdoor unit heat exchanger switching control.

[Description of Signs] Cd condenser Ev Evaporator N1 to N5 Heat exchanger ex1 to ex5 Expansion means 103 Control means

Claims (2)

(57) [Claims] 1. A state in which a high-pressure gas refrigerant supply path and a condensed refrigerant outlet path are communicated with heat exchangers (N1 to N5) so that the heat exchangers (N1 to N5) function as condensers (Cd). The expansion refrigerant supply path from the expansion means (ex1 to ex5) and the low pressure gas refrigerant discharge path to the heat exchanger (N1 to N5).
A heat pump device provided with control means (103) for switching and controlling a refrigerant path so that the heat exchangers (N1 to N5) function as evaporators (Ev). (103) is the heat exchanger (N1 to N
5) When switching from the state of functioning as the condenser (Cd) to the state of functioning as the evaporator (Ev), the high-pressure gas refrigerant supply path, the condensed refrigerant discharge path, the expansion refrigerant supply path, and the low-pressure gas refrigerant discharge are performed. After all of the paths are in a non-communication state with respect to the heat exchangers (N1 to N5), the low-pressure gas refrigerant outlet path precedes the expanded refrigerant supply path with respect to the heat exchangers (N1 to N5). And then connect the expanded refrigerant supply path to the heat exchanger (N1 to N5).
A heat pump device configured to communicate with the heat pump. 2. A state in which a high-pressure gas refrigerant supply path and a condensed refrigerant outlet path are communicated with heat exchangers (N1 to N5) so that the heat exchangers (N1 to N5) function as condensers (Cd). The expansion refrigerant supply path from the expansion means (ex1 to ex5) and the low pressure gas refrigerant discharge path to the heat exchanger (N1 to N5).
A heat pump device provided with control means (103) for switching and controlling a refrigerant path so that the heat exchangers (N1 to N5) function as evaporators (Ev). (103) is the heat exchanger (N1 to N
5) When switching from the state of functioning as the evaporator (Ev) to the state of functioning as the condenser (Cd) is performed, the high-pressure gas refrigerant supply path, the condensed refrigerant discharge path, the expansion refrigerant supply path, and the low-pressure gas refrigerant discharge. After all of the paths are not in communication with the heat exchangers (N1 to N5), the high-pressure gas refrigerant supply path precedes the condensed refrigerant outlet path to the heat exchangers (N1 to N5). And then the condensed refrigerant outlet path to the heat exchanger (N1 to N5).
A heat pump device configured to communicate with the heat pump.